Mechanism for operating rolling metallic shutters.



L. G. WILSON.

MEGHANISM FOE OPERATING ROLLING METALLIC SHUTTBRS.

APPLICATION FILED JUNE 22, 190B.

Patented Aug. 3, 1909.

2 SHEETS-SHEET 1.

- wmyEssEs: A? W ATTORNEYS L. G. WILSON. MECHANISM FOR OPERATING ROLLINGMETALLIC SHUTTERS.

APPLICATION FILED JUNE 22, 1908.

929,742. Patented Aug. 3. 1909.

2 SHEETSSEBIJT 2,

INVENTOR 1.155756 G. W/L50/v.

WITNESSES:

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ATTORNEYS LESTER G. WILSON, OF LARCHMONT, NEW YORK.

MEGHANISM FOR OPERATING ROLLING METALLIO'BHUTTERS.

' Specification of Letters Patent.

Patented Aug. '3, 1909.

Application filed'J'une 22, 1908. Serial No. 439,882.

the means employed for raisingand lowering the large corrugated metal orinterlocking slat shutters now so generally used to protect the doorsand windows of large buildings at night, and when not in regular use,and is especially useful when the shaft u on which such shutter isrolled or unrolle is placed below instead of above in which case theshutter-must be drawn up to close and let down to open.

The object of my invention isto arrange a shutter of the above describedtype Which may be readily opened or closed, and which may be stopped atany desired point; which will require a minimumof effort to operate it,when the proper means is employed, but which is positively locked andcannot be moved howevergreat the force otherwise applied; in which theshutter is always tightly stretched; and in which the operatingmechanism, is simple, substantial, and not easily deranged.

My invention will be best understood by reference to the drawings Where-Figure 1 is an elevation looking from the rear, or inside, of a metalshutter fitted with my improved operating mechanism. Fig.2 is asectional elevation along the line (Ir-'1) of Fig.'1- and Fig. 3 is aplan, part in section,' along the line cd through the: axis of theshutter roller, the view being taken from above, and the shutter itselfbeing omitted.

1 is ashutter of corrugated iron or steel fixedlyattache'd to barrels 2,2, 2, and adapted to open and close awindow opening 3; the edge or endof the curtain is providedwith a bar, 4, operating to make a closemechanical joint with the to of the=wi-ndow frame when the shutter iscosed, as also to stiffen and protect the end of the shutter.

. Attached to the window ire-meat one side. is :a worm gear, 5, composedof a worm, -6,

engaging a wheel, 7, WhlCl'l is carried by the shaft, -8,-bearing at itsother extremitya s rocket wheel, At the top of the-winow frame ismounted a shaft, 10,- carry-in sprocket wheels lland 12, fixedly-attacheto each end; these Wheels lie in planes intersecting that ofthe curtainnear the outer edges of the runways, 13 and 14-, in which the curtainmoves and one of these planes, that of sprocket wheel 12, is also thatof the worm gear sprocket wheel, 9. The peripheries of these sprocketwheels project into the runways approximately to their central plane.Shaft 10 itself is hollow and has, at one end, a journal 12 fixedlyattached thereto and working in asuitable journal box setin the side ofth shutter frame or opening. At the other end of the hollow shaft is asuitably formed-plug 11 also fixedly attached; thisplug has the sprocketwheel 11 exteriorly V eyed to it and is centrally bored to receive ashort shaft section 11 itself firmly keyed to a wall socket 11 by a pin12 upon which shaft section it is free to rotate. A coiled spring 1 1 ofselected strength is fixed,at one end to the shaft section 11 and, atthe other end, to an internal plug 12 'riveted or keyed straight downtobe fixedly attached to the periphery of a-fla-n edpulley, 17, keyed-toone end of the barre shaft, 18, and the other 16 beingsimilarly-attached to a second flan ed.pu1ley,"19, identical with 17andsimi arly fastened to the shaft, 18', the chain first passing back,however, over the worm gearsprocket, 9, and engaging therewith.

The shutter roller consists ofa shaft 18, which is attached to thewindow frameby suitable bearings, 20, 20, and besides carr v-. ing thepulleys, 17, and 19, also supports the barrels 2, 2, 2, to'which theinner shutter end is fastened and upon: and from which the shutter isrolled. These rollers may be thought of as relatively thin flat diskswith a centraL-hub 2 on one side and a flatenipheral rim 2*- on theother, the hub belng bored for-an easy fit over shaft 10 and the otherdiameter of the rim'being gradually decreasedover a segment of itscircumfer ence un til it meets a radial :and axial shoulder, 21, .aainst which the curtain end is abutted; t 's construction causes therolling and :un-ro'lling of the curtain upon its barrels I riability inthe necessary applied power which would Otherwise result. Collars, 22,22, retain the rollers in their correct axial position. Inclosed withinthe rim of each rollerand attached to it at 23 is a spiral spring, 24,preferably of flat material, so selected as to have a suitable number ofturns and tension; the inn'er'end of this spring is attached to shaft 18at 25. The barrels 2, 2, 2, may, therefore, turn in either directionupon shaft 18 against the resistance of spring 24, within limitsdetgrmined by the length of the spring, its tension, and the torsionalforce applied. Suppose, now, the curtain to be down or open. To raise itI rotate the hand wheel, 26, carried by the worm gear shaft, 8

in the proper direction, thereby pulling u on the curtain end throughtheinstrumenta 'ty of the sprocket chains and causing the curtain tounwindfrom the barrels 2, 2, 2; the shaft 18, through the springs, 24,will also rotate tending thereby to wind upon the pulleys 17,. 19, thatlength of sprocket chain which is released by the unwinding of thecurtain.

The shutter 1 is, necessarily, of considerable thickness so that thediameter and consequent circumference of'the cylinder which is formed asit rolls'and unrolls, changes very rapidly and has minimum and maximumlimits widely difierent. When the curtain begins to rise thiscircumference is greatest but continuously decreases as the curtain isunrolled until, finally, when-the latter is fully closed, it becomesleast. The effect of this is, that for successive revolutions of theshutter barrels the length of the shutter unrolled and, hence the lengthof sprocket chain to be wound uponthepulleys, 17, 19, becomes less andless. But since the sprocket chain itself has material thickness itmust, as it winds upon these pulleys, steadily increase the effectivediameter of the cylinder uponwhich it, itself, rolls. An actuallygreater length of chain is therefore required for each succes siverevolution of the pulleys. By using the previously described springconnection between the rollers 2, 2, 2, and the shaft v18,

' these just mentioned opposing conditions are reconciled inasmuch asthis shaft need not revolve with the same angular velocity as therollers, but is free to turn relatively thereto,

' while tending continually to rotate, there fore, in the same directionas the roller it will, in fact, only rotate sufficiently in amount tohold the chain and shutter taut.

The relative rotative movement of the pulleys and the barrels may becontinuously in the one direction or the other, as the shutter rolls orunrolls, or part1 in the one direction and partly in the ot er; thisdepends largely upon the diameter of the pulleys with reference to thediameter of the rolled shutter. If the pulley diameter is less than thatof the fully rolled shutter the pulleys will,

rotate more rapidly than the rollers until such time as the decreasingdiameter of the rolled shutter shall become equal to the increasingdiameter of the chain wound pulleys after which the pulleys will revolveless ra idly than the curtain rollers. I pu leys be of greater diameterthan the fully Should the rolled shutter they will, of course, revolvethe coiled shutter whenthe latter is about half'unwound and with sometension on the rings, 24, at this point. In this way, as the s sliutterbegins to unroll, the pulleys move relatively to the shaft so as tolessen the spring tension to a minimum when the shutter reaches itsmidway position, after which the relative directionof movement isreversed so as to restore the spring tension to a maximum as the shutteris furtherunrolled to its limit. It should be noted that the barextensions 15, 15, to which the chains 16, 16 are attached are wellbelow the to of the bar; this is so that the top flat of the ar may befirmly seated against the underside of the top of the shutter openingbefore the attaching points of the chain and bar begin to'turn over theto of the sprocket wheels and out of the vertlcal plane of the curtain.As explained, there is always tension upon the springs 24, so that, nomatter in what position, their tendency is at all times, to coil theshutter upon the barrels. This keeps the shutter front. stretched andsmooth and so as to always present a good appearment upon the shutterbarrels, tending always to coil the shutter, must be established and isaided by the s ring 11* of the top shaft 10 which I set so that it has,always, a tendency to. raise the shutter. This setting 1s easily accomlished by thrusting a pin into diametral ho cs 13 and using this pin asa lever to rotate the shaft 11 joined to the end of the spring, the keypin 12 being adapted to fit any one of a number of similar diametralholes placed in the shaft for its reception. The direction of rotationis so chosen that s ring 11 has minimum tension when the s utter s up orfully closed but is increased as the shutter is lowered.

By employing a' properly proportioned worm gear as an operative means,the shutter may be raised or lowered with ease no matter how large ormassive it may be; being an irreversible device, however, the shuttercan not be operated by my force, however, great, applied elsewhere orfrom the outside.

rmaintained. This stretching of the shutter fore, for light orventilation without fear of casual trespassers since it may not be movedfrom the outside and does not afford an easy footing for climbers.

I may, if I choose, substitute for the upper spring shaft 10 asdescribed, an ordinary straight shaft with sprocket wheels firmly fixedthereto and Imay also vary many of the details of design andconstruction in my invention without departing from its true spirit, andnow, having described its pre-' ferred embodiment,

I claim:

1. In a flexible metallic shutter having one end attached to and adaptedto coil upon a roller; journals within said roller and elasticallyattached thereto; and means attached to the journals and to the free endof the shutter and cooperating with an irreversible driving devicewhereby the shutter may be operated.

2. In a flexible metallic shutter havingone end attached to and adaptedto oil upon a roller; journals within said rolle and elasticallyattached thereto; means guided by overhead pulleys and attached to saidjournals and t e free end of said shutter; and an irreversible drivingdevice cooperating with said means and adapted to operate the shutter.

3. In a flexible metallic shutter having one end attached to barrels andadapted to coil thereon, a shaft assing through the center of eachbarrel am elastically attached thereto; pulleys fixedly attached to theends of said shaft; sprocket chains cooperating with overhead sprocketwheels and attached, as

, to one end, to theeriphery of each pulley the other ends 0 sa1d chainsbeing attached to, the free end of the shutter; and

an irreversible driving device engaging one of said sprocket chains andadapted to oper- I ate the curtain.

4. In a flexible metallic shutter having one end attached to barrels andadapted to coil thereon, a shaft assing'through the center of eachbarrel and elastically attached thereto; flanged pulleys fixedlyattached to the ends of said shaft; s rocket chains cooperating withoverhead wheels and attached, as 'to one end, to the periphery of eachpulley the other ends of said chains being attached to the free end ofthe shutter; and a sprocket wheel driven by a worm gear enga ing one ofsaid sprocket chains, whereby sai curtain may be raised or lowered.

5. In a flexible metallic shutter having one end attached to barrels andadapted to coil thereon, a shaft through the center of each barrel andelasticallyl. attached thereto;

'flanged pulleys fixedly attached to the ends of said shaft; overhead srocket wheels fixedly related to one anot er and having torsional s ringconnection with fixed centers upon whic they rotate; sprocket chainscooperating with said overhead sprocket wheels and attached, as to oneend, to the peri hery of each pulley the other ends of said c ll'ains.being attached to the free end of the shutter; and a sprocket wheeldriven by a worm gear engaging one of said sprocket chains, whereby saidcurtain may be raised or lowered.

In testimony whereof I have hereunto set my hand in the presence of twosubscribing witnesses.

LESTER G. WILSON.

Witnesses: ELMER SHIRLYOUNG, JOHN A. KEHLENBEGK.

